xhci: tegra: run firmware log thread only if need

xhci: tegra: run firmware log thread only if need

Driver doesn't need to run a kernel thread to collect firmware log
if release build firmware is loaded. Only debug build firmware is
capable of generating logs. This commit checks firmware CFGTBL to
know whether a firmware generates logs or not.

bug 1487603

Change-Id: I8b147710dae58332d68625fedd3173e2d2f6074b
Signed-off-by: JC Kuo <jckuo@nvidia.com>
Reviewed-on: http://git-master/r/663769
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: David Lim <dlim@nvidia.com>
Reviewed-by: Ajay Gupta <ajayg@nvidia.com>
Reviewed-by: Ashutosh Jha <ajha@nvidia.com>